[PATCH v7 0/4] firmware: ti_sci: Introduce BOARDCFG_MANAGED mode for Jacinto family

[PATCH v7 0/4] firmware: ti_sci: Introduce BOARDCFG_MANAGED mode for Jacinto family

[Thomas Richard (TI)]

This is the 7th iteration of this series. I did some changes as suggested
by Nishanth. In ti_sci driver I added a lock around set_irq() and
free_irq() to keep hash list consistent in case of concurrent accesses, and
now ti_sci driver tries to restore all IRQs even in case of error.
On the clock side, get_parent() errors are now handled. If we fail to get
parent_id for a clock, set_parent() is not called anymore in
restore_context().
Other minor changes are listed in the changelog.

Best Regards,
Thomas

Signed-off-by: Thomas Richard (TI) <thomas.richard@bootlin.com>
---
Changes in v7:
- ti_sci: add a lock around set_irq() and free_irq() to keep hash list
  consistent.
- ti_sci: in free_irq() add warning in case we are in a path that shall not
  be run.
- ti_sci: free an IRQ if we failed to add it in the hash list.
- ti_sci: during resume in case of error, try to restore remaining IRQs and
  logs all errors, then return the latest one.
- sci-clk: add Stephen's AB tag and Brian's RB tag.
- sci-clk: handle get_parent() error, in restore_context() do not call
  set_parent() with parent_id=0 if get_parent() failed.
- Link to v6: https://lore.kernel.org/r/20260427-ti-sci-jacinto-s2r-restore-irq-v6-0-72c6468cb2ab@bootlin.com

Changes in v6:
- rebase on v7.1-rc1.
- add Kendall's RB tag.
- sci-clk: call set_parent() during restore_context() only for clocks which
  have more than one parent.
- sci-clk: save also rate returned by recalc_rate().
- Link to v5: https://lore.kernel.org/r/20260407-ti-sci-jacinto-s2r-restore-irq-v5-0-97b28f2d93f9@bootlin.com

Changes in v5:
- rebase on v7.0-rc7.
- add Dhruva's RB tag.
- use kzalloc_obj() in ti_sci driver.
- Link to v4: https://lore.kernel.org/r/20260204-ti-sci-jacinto-s2r-restore-irq-v4-0-67820af39eac@bootlin.com

Changes in v4:
- rebase on linux-next next-20260202.
- fix BOARDCFG_MANAGED value.
- add MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST firmware capability.
- add MSG_FLAG_CAPS_LPM_CLK_CONTEXT_LOST firmware capability.
- Link to v3: https://lore.kernel.org/r/20251205-ti-sci-jacinto-s2r-restore-irq-v3-0-d06963974ad4@bootlin.com

Changes in v3:
- rebased on linux-next
- sci-clk: context_restore() operation restores also rate.
- Link to v2: https://lore.kernel.org/r/20251127-ti-sci-jacinto-s2r-restore-irq-v2-0-a487fa3ff221@bootlin.com

Changes in v2:
- ti_sci: use hlist to store IRQs.
- sci-clk: add context_restore operation
- ti_sci: restore clock parents during resume
- Link to v1: https://lore.kernel.org/r/20251017-ti-sci-jacinto-s2r-restore-irq-v1-0-34d4339d247a@bootlin.com

---
Thomas Richard (TI) (4):
      firmware: ti_sci: add BOARDCFG_MANAGED mode support
      firmware: ti_sci: add support for restoring IRQs during resume
      clk: keystone: sci-clk: add restore_context() operation
      firmware: ti_sci: add support for restoring clock context during resume

 drivers/clk/keystone/sci-clk.c |  45 +++++++--
 drivers/firmware/ti_sci.c      | 212 ++++++++++++++++++++++++++++++++++++++---
 drivers/firmware/ti_sci.h      |   6 ++
 3 files changed, 242 insertions(+), 21 deletions(-)
---
base-commit: a8afe52b5e5050c0c5825d7931a21b687a628d9a
change-id: 20251010-ti-sci-jacinto-s2r-restore-irq-428e008fd10c

Best regards,
-- 
Thomas Richard (TI) <thomas.richard@bootlin.com>

[PATCH v7 1/4] firmware: ti_sci: add BOARDCFG_MANAGED mode support

[Thomas Richard (TI)]

In BOARDCFG_MANAGED mode, the low power mode configuration is done
statically for the DM via the boardcfg. Constraints are not supported, and
prepare_sleep() is not needed.

Reviewed-by: Dhruva Gole <d-gole@ti.com>
Reviewed-by: Kendall Willis <k-willis@ti.com>
Signed-off-by: Thomas Richard (TI) <thomas.richard@bootlin.com>
---
 drivers/firmware/ti_sci.c | 10 +++++++---
 drivers/firmware/ti_sci.h |  2 ++
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index dd9911b1cc11..eaeaaae94142 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -3772,8 +3772,11 @@ static int ti_sci_prepare_system_suspend(struct ti_sci_info *info)
 			return ti_sci_cmd_prepare_sleep(&info->handle,
 							TISCI_MSG_VALUE_SLEEP_MODE_DM_MANAGED,
 							0, 0, 0);
+		} else if (info->fw_caps & MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED) {
+			/* Nothing to do in the BOARDCFG_MANAGED mode */
+			return 0;
 		} else {
-			/* DM Managed is not supported by the firmware. */
+			/* DM Managed and BoardCfg Managed are not supported by the firmware. */
 			dev_err(info->dev, "Suspend to memory is not supported by the firmware\n");
 			return -EOPNOTSUPP;
 		}
@@ -4011,12 +4014,13 @@ static int ti_sci_probe(struct platform_device *pdev)
 	}
 
 	ti_sci_msg_cmd_query_fw_caps(&info->handle, &info->fw_caps);
-	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s\n",
+	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s%s\n",
 		info->fw_caps & MSG_FLAG_CAPS_GENERIC ? "Generic" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_PARTIAL_IO ? " Partial-IO" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_DM_MANAGED ? " DM-Managed" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_ABORT ? " LPM-Abort" : "",
-		info->fw_caps & MSG_FLAG_CAPS_IO_ISOLATION ? " IO-Isolation" : ""
+		info->fw_caps & MSG_FLAG_CAPS_IO_ISOLATION ? " IO-Isolation" : "",
+		info->fw_caps & MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED ? " BoardConfig-Managed" : ""
 	);
 
 	ti_sci_setup_ops(info);
diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
index 4616127e33ff..d90de59e29eb 100644
--- a/drivers/firmware/ti_sci.h
+++ b/drivers/firmware/ti_sci.h
@@ -150,6 +150,7 @@ struct ti_sci_msg_req_reboot {
  *		MSG_FLAG_CAPS_LPM_DM_MANAGED: LPM can be managed by DM
  *		MSG_FLAG_CAPS_LPM_ABORT: Abort entry to LPM
  *		MSG_FLAG_CAPS_IO_ISOLATION: IO Isolation support
+ *		MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED: LPM config done statically for the DM via boardcfg
  *
  * Response to a generic message with message type TI_SCI_MSG_QUERY_FW_CAPS
  * providing currently available SOC/firmware capabilities. SoC that don't
@@ -162,6 +163,7 @@ struct ti_sci_msg_resp_query_fw_caps {
 #define MSG_FLAG_CAPS_LPM_DM_MANAGED	TI_SCI_MSG_FLAG(5)
 #define MSG_FLAG_CAPS_LPM_ABORT		TI_SCI_MSG_FLAG(9)
 #define MSG_FLAG_CAPS_IO_ISOLATION	TI_SCI_MSG_FLAG(7)
+#define MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED	TI_SCI_MSG_FLAG(12)
 #define MSG_MASK_CAPS_LPM		GENMASK_ULL(4, 1)
 	u64 fw_caps;
 } __packed;

-- 
2.53.0

Re: [PATCH v7 1/4] firmware: ti_sci: add BOARDCFG_MANAGED mode support

[Nishanth Menon]

On 10:35-20260506, Thomas Richard (TI) wrote:
> In BOARDCFG_MANAGED mode, the low power mode configuration is done
> statically for the DM via the boardcfg. Constraints are not supported, and
> prepare_sleep() is not needed.
> 

minor nit:
[..]
> diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
> index 4616127e33ff..d90de59e29eb 100644
> --- a/drivers/firmware/ti_sci.h
> +++ b/drivers/firmware/ti_sci.h
> @@ -150,6 +150,7 @@ struct ti_sci_msg_req_reboot {
>   *		MSG_FLAG_CAPS_LPM_DM_MANAGED: LPM can be managed by DM
>   *		MSG_FLAG_CAPS_LPM_ABORT: Abort entry to LPM
>   *		MSG_FLAG_CAPS_IO_ISOLATION: IO Isolation support
> + *		MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED: LPM config done statically for the DM via boardcfg

will be good to keep this under 100 chars

>   *
>   * Response to a generic message with message type TI_SCI_MSG_QUERY_FW_CAPS
>   * providing currently available SOC/firmware capabilities. SoC that don't
> @@ -162,6 +163,7 @@ struct ti_sci_msg_resp_query_fw_caps {
>  #define MSG_FLAG_CAPS_LPM_DM_MANAGED	TI_SCI_MSG_FLAG(5)
>  #define MSG_FLAG_CAPS_LPM_ABORT		TI_SCI_MSG_FLAG(9)
>  #define MSG_FLAG_CAPS_IO_ISOLATION	TI_SCI_MSG_FLAG(7)
> +#define MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED	TI_SCI_MSG_FLAG(12)
>  #define MSG_MASK_CAPS_LPM		GENMASK_ULL(4, 1)
>  	u64 fw_caps;
>  } __packed;
> 
> -- 
> 2.53.0
> 

-- 
Regards,
Nishanth Menon
Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3  1A34 DDB5 849D 1736 249D
https://ti.com/opensource

[PATCH v7 2/4] firmware: ti_sci: add support for restoring IRQs during resume

[Thomas Richard (TI)]

Some DM-Firmware are not able to restore the IRQ context after a
suspend-resume. The IRQ_CONTEXT_LOST firmware capability has been
introduced to identify this characteristic. In this case the
responsibility is delegated to the ti_sci driver, which maintains an
internal list of all requested IRQs. This list is updated on each
set()/free() operation, and all IRQs are restored during the resume_noirq()
phase.

Reviewed-by: Dhruva Gole <d-gole@ti.com>
Reviewed-by: Kendall Willis <k-willis@ti.com>
Signed-off-by: Thomas Richard (TI) <thomas.richard@bootlin.com>
---
 drivers/firmware/ti_sci.c | 201 +++++++++++++++++++++++++++++++++++++++++++---
 drivers/firmware/ti_sci.h |   2 +
 2 files changed, 191 insertions(+), 12 deletions(-)

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index eaeaaae94142..531ac3aa38b8 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -12,11 +12,13 @@
 #include <linux/cpu.h>
 #include <linux/debugfs.h>
 #include <linux/export.h>
+#include <linux/hashtable.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/mailbox_client.h>
 #include <linux/module.h>
+#include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
@@ -87,6 +89,16 @@ struct ti_sci_desc {
 	int max_msg_size;
 };
 
+/**
+ * struct ti_sci_irq - Description of allocated irqs
+ * @node: Link to hash table
+ * @desc: Description of the irq
+ */
+struct ti_sci_irq {
+	struct hlist_node node;
+	struct ti_sci_msg_req_manage_irq desc;
+};
+
 /**
  * struct ti_sci_info - Structure representing a TI SCI instance
  * @dev:	Device pointer
@@ -101,6 +113,8 @@ struct ti_sci_desc {
  * @chan_rx:	Receive mailbox channel
  * @minfo:	Message info
  * @node:	list head
+ * @irqs:	List of allocated irqs
+ * @irq_lock:	Protection for irq hash list
  * @host_id:	Host ID
  * @fw_caps:	FW/SoC low power capabilities
  * @users:	Number of users of this instance
@@ -118,6 +132,8 @@ struct ti_sci_info {
 	struct mbox_chan *chan_rx;
 	struct ti_sci_xfers_info minfo;
 	struct list_head node;
+	DECLARE_HASHTABLE(irqs, 8);
+	struct mutex irq_lock;
 	u8 host_id;
 	u64 fw_caps;
 	/* protected by ti_sci_list_mutex */
@@ -2301,6 +2317,32 @@ static int ti_sci_manage_irq(const struct ti_sci_handle *handle,
 	return ret;
 }
 
+/**
+ * ti_sci_irq_hash() - Helper API to compute irq hash for the hash table.
+ * @irq:	irq to hash
+ *
+ * Return: the computed hash value.
+ */
+static int ti_sci_irq_hash(struct ti_sci_msg_req_manage_irq *irq)
+{
+	return irq->src_id ^ irq->src_index;
+}
+
+/**
+ * ti_sci_irq_equal() - Helper API to compare two irqs (generic headers are not
+ *                       compared)
+ * @irq_a:	irq_a to compare
+ * @irq_b:	irq_b to compare
+ *
+ * Return: true if the two irqs are equal, else false.
+ */
+static bool ti_sci_irq_equal(struct ti_sci_msg_req_manage_irq *irq_a,
+			     struct ti_sci_msg_req_manage_irq *irq_b)
+{
+	return !memcmp(&irq_a->valid_params, &irq_b->valid_params,
+		       sizeof(*irq_a) - sizeof(irq_a->hdr));
+}
+
 /**
  * ti_sci_set_irq() - Helper api to configure the irq route between the
  *		      requested source and destination
@@ -2324,15 +2366,60 @@ static int ti_sci_set_irq(const struct ti_sci_handle *handle, u32 valid_params,
 			  u16 dst_host_irq, u16 ia_id, u16 vint,
 			  u16 global_event, u8 vint_status_bit, u8 s_host)
 {
+	struct ti_sci_info *info = handle_to_ti_sci_info(handle);
+	struct ti_sci_msg_req_manage_irq *desc;
+	struct ti_sci_irq *irq;
+	int ret;
+
+	/*
+	 * Lock for set_irq() and free_irq() to keep the IRQ hash list
+	 * consistent only if MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST is set. Else
+	 * IRQ hash list is not used.
+	 */
+	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST)
+		mutex_lock(&info->irq_lock);
+
 	pr_debug("%s: IRQ set with valid_params = 0x%x from src = %d, index = %d, to dst = %d, irq = %d,via ia_id = %d, vint = %d, global event = %d,status_bit = %d\n",
 		 __func__, valid_params, src_id, src_index,
 		 dst_id, dst_host_irq, ia_id, vint, global_event,
 		 vint_status_bit);
 
-	return ti_sci_manage_irq(handle, valid_params, src_id, src_index,
-				 dst_id, dst_host_irq, ia_id, vint,
-				 global_event, vint_status_bit, s_host,
-				 TI_SCI_MSG_SET_IRQ);
+	ret = ti_sci_manage_irq(handle, valid_params, src_id, src_index,
+				dst_id, dst_host_irq, ia_id, vint,
+				global_event, vint_status_bit, s_host,
+				TI_SCI_MSG_SET_IRQ);
+
+	if (ret || !(info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST))
+		goto end;
+
+	irq = kzalloc_obj(*irq, GFP_KERNEL);
+	if (!irq) {
+		ti_sci_manage_irq(handle, valid_params, src_id, src_index,
+				  dst_id, dst_host_irq, ia_id, vint,
+				  global_event, vint_status_bit, s_host,
+				  TI_SCI_MSG_FREE_IRQ);
+		ret = -ENOMEM;
+		goto end;
+	}
+
+	desc = &irq->desc;
+	desc->valid_params = valid_params;
+	desc->src_id = src_id;
+	desc->src_index = src_index;
+	desc->dst_id = dst_id;
+	desc->dst_host_irq = dst_host_irq;
+	desc->ia_id = ia_id;
+	desc->vint = vint;
+	desc->global_event = global_event;
+	desc->vint_status_bit = vint_status_bit;
+	desc->secondary_host = s_host;
+
+	hash_add(info->irqs, &irq->node, ti_sci_irq_hash(desc));
+
+end:
+	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST)
+		mutex_unlock(&info->irq_lock);
+	return ret;
 }
 
 /**
@@ -2358,15 +2445,56 @@ static int ti_sci_free_irq(const struct ti_sci_handle *handle, u32 valid_params,
 			   u16 dst_host_irq, u16 ia_id, u16 vint,
 			   u16 global_event, u8 vint_status_bit, u8 s_host)
 {
+	struct ti_sci_info *info = handle_to_ti_sci_info(handle);
+	struct ti_sci_msg_req_manage_irq irq_desc;
+	struct device *dev = info->dev;
+	struct ti_sci_irq *this_irq;
+	struct hlist_node *tmp_node;
+	int ret;
+
+	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST)
+		mutex_lock(&info->irq_lock);
+
 	pr_debug("%s: IRQ release with valid_params = 0x%x from src = %d, index = %d, to dst = %d, irq = %d,via ia_id = %d, vint = %d, global event = %d,status_bit = %d\n",
 		 __func__, valid_params, src_id, src_index,
 		 dst_id, dst_host_irq, ia_id, vint, global_event,
 		 vint_status_bit);
 
-	return ti_sci_manage_irq(handle, valid_params, src_id, src_index,
-				 dst_id, dst_host_irq, ia_id, vint,
-				 global_event, vint_status_bit, s_host,
-				 TI_SCI_MSG_FREE_IRQ);
+	ret = ti_sci_manage_irq(handle, valid_params, src_id, src_index,
+				dst_id, dst_host_irq, ia_id, vint,
+				global_event, vint_status_bit, s_host,
+				TI_SCI_MSG_FREE_IRQ);
+
+	if (ret || !(info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST))
+		goto end;
+
+	irq_desc.valid_params = valid_params;
+	irq_desc.src_id = src_id;
+	irq_desc.src_index = src_index;
+	irq_desc.dst_id = dst_id;
+	irq_desc.dst_host_irq = dst_host_irq;
+	irq_desc.ia_id = ia_id;
+	irq_desc.vint = vint;
+	irq_desc.global_event = global_event;
+	irq_desc.vint_status_bit = vint_status_bit;
+	irq_desc.secondary_host = s_host;
+
+	hash_for_each_possible_safe(info->irqs, this_irq, tmp_node, node,
+				    ti_sci_irq_hash(&irq_desc)) {
+		if (ti_sci_irq_equal(&irq_desc, &this_irq->desc)) {
+			hlist_del(&this_irq->node);
+			kfree(this_irq);
+			goto end;
+		}
+	}
+
+	dev_warn(dev, "%s: should not be here, IRQ was not found in hash list\n",
+		 __func__);
+
+end:
+	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST)
+		mutex_unlock(&info->irq_lock);
+	return ret;
 }
 
 /**
@@ -3847,7 +3975,10 @@ static int ti_sci_suspend_noirq(struct device *dev)
 static int ti_sci_resume_noirq(struct device *dev)
 {
 	struct ti_sci_info *info = dev_get_drvdata(dev);
-	int ret = 0;
+	struct ti_sci_msg_req_manage_irq *irq_desc;
+	struct ti_sci_irq *irq;
+	struct hlist_node *tmp_node;
+	int ret = 0, err = 0, i;
 	u32 source;
 	u64 time;
 	u8 pin;
@@ -3859,13 +3990,50 @@ static int ti_sci_resume_noirq(struct device *dev)
 			return ret;
 	}
 
+	switch (pm_suspend_target_state) {
+	case PM_SUSPEND_MEM:
+		if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST) {
+			hash_for_each_safe(info->irqs, i, tmp_node, irq, node) {
+				irq_desc = &irq->desc;
+				ret = ti_sci_manage_irq(&info->handle,
+							irq_desc->valid_params,
+							irq_desc->src_id,
+							irq_desc->src_index,
+							irq_desc->dst_id,
+							irq_desc->dst_host_irq,
+							irq_desc->ia_id,
+							irq_desc->vint,
+							irq_desc->global_event,
+							irq_desc->vint_status_bit,
+							irq_desc->secondary_host,
+							TI_SCI_MSG_SET_IRQ);
+				if (ret) {
+					dev_err(dev, "failed to restore IRQ with valid_params = 0x%x from src = %d, index = %d, to dst = %d, irq = %d,via ia_id = %d, vint = %d, global event = %d,status_bit = %d\n",
+						irq_desc->valid_params,
+						irq_desc->src_id,
+						irq_desc->src_index,
+						irq_desc->dst_id,
+						irq_desc->dst_host_irq,
+						irq_desc->ia_id,
+						irq_desc->vint,
+						irq_desc->global_event,
+						irq_desc->vint_status_bit);
+					err = ret;
+				}
+			}
+		}
+		break;
+	default:
+		break;
+	}
+
 	ret = ti_sci_msg_cmd_lpm_wake_reason(&info->handle, &source, &time, &pin, &mode);
 	/* Do not fail to resume on error as the wake reason is not critical */
 	if (!ret)
 		dev_info(dev, "ti_sci: wakeup source:0x%x, pin:0x%x, mode:0x%x\n",
 			 source, pin, mode);
 
-	return 0;
+	return err;
 }
 
 static void ti_sci_pm_complete(struct device *dev)
@@ -4014,13 +4182,14 @@ static int ti_sci_probe(struct platform_device *pdev)
 	}
 
 	ti_sci_msg_cmd_query_fw_caps(&info->handle, &info->fw_caps);
-	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s%s\n",
+	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s%s%s\n",
 		info->fw_caps & MSG_FLAG_CAPS_GENERIC ? "Generic" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_PARTIAL_IO ? " Partial-IO" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_DM_MANAGED ? " DM-Managed" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_ABORT ? " LPM-Abort" : "",
 		info->fw_caps & MSG_FLAG_CAPS_IO_ISOLATION ? " IO-Isolation" : "",
-		info->fw_caps & MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED ? " BoardConfig-Managed" : ""
+		info->fw_caps & MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED ? " BoardConfig-Managed" : "",
+		info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST ? " IRQ-Context-Lost" : ""
 	);
 
 	ti_sci_setup_ops(info);
@@ -4053,6 +4222,14 @@ static int ti_sci_probe(struct platform_device *pdev)
 	list_add_tail(&info->node, &ti_sci_list);
 	mutex_unlock(&ti_sci_list_mutex);
 
+	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST) {
+		ret = devm_mutex_init(dev, &info->irq_lock);
+		if (ret)
+			return ret;
+
+		hash_init(info->irqs);
+	}
+
 	ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
 	if (ret) {
 		dev_err(dev, "platform_populate failed %pe\n", ERR_PTR(ret));
diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
index d90de59e29eb..67f16e8c69a1 100644
--- a/drivers/firmware/ti_sci.h
+++ b/drivers/firmware/ti_sci.h
@@ -151,6 +151,7 @@ struct ti_sci_msg_req_reboot {
  *		MSG_FLAG_CAPS_LPM_ABORT: Abort entry to LPM
  *		MSG_FLAG_CAPS_IO_ISOLATION: IO Isolation support
  *		MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED: LPM config done statically for the DM via boardcfg
+ *		MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST: DM is not able to restore IRQ context
  *
  * Response to a generic message with message type TI_SCI_MSG_QUERY_FW_CAPS
  * providing currently available SOC/firmware capabilities. SoC that don't
@@ -164,6 +165,7 @@ struct ti_sci_msg_resp_query_fw_caps {
 #define MSG_FLAG_CAPS_LPM_ABORT		TI_SCI_MSG_FLAG(9)
 #define MSG_FLAG_CAPS_IO_ISOLATION	TI_SCI_MSG_FLAG(7)
 #define MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED	TI_SCI_MSG_FLAG(12)
+#define MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST	TI_SCI_MSG_FLAG(14)
 #define MSG_MASK_CAPS_LPM		GENMASK_ULL(4, 1)
 	u64 fw_caps;
 } __packed;

-- 
2.53.0

Re: [PATCH v7 2/4] firmware: ti_sci: add support for restoring IRQs during resume

[Nishanth Menon]

On 10:35-20260506, Thomas Richard (TI) wrote:
> Some DM-Firmware are not able to restore the IRQ context after a
> suspend-resume. The IRQ_CONTEXT_LOST firmware capability has been
> introduced to identify this characteristic. In this case the
> responsibility is delegated to the ti_sci driver, which maintains an
> internal list of all requested IRQs. This list is updated on each
> set()/free() operation, and all IRQs are restored during the resume_noirq()
> phase.
> 
> Reviewed-by: Dhruva Gole <d-gole@ti.com>
> Reviewed-by: Kendall Willis <k-willis@ti.com>
> Signed-off-by: Thomas Richard (TI) <thomas.richard@bootlin.com>
> ---

coccicheck reports two additional warnings at this patch:
+drivers/firmware/ti_sci.c:2495:1-7: preceding lock on line 2454
+drivers/firmware/ti_sci.c:2420:1-7: preceding lock on line 2378

>  drivers/firmware/ti_sci.c | 201 +++++++++++++++++++++++++++++++++++++++++++---
>  drivers/firmware/ti_sci.h |   2 +
>  2 files changed, 191 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
> index eaeaaae94142..531ac3aa38b8 100644
> --- a/drivers/firmware/ti_sci.c
> +++ b/drivers/firmware/ti_sci.c
> @@ -12,11 +12,13 @@
>  #include <linux/cpu.h>
>  #include <linux/debugfs.h>
>  #include <linux/export.h>
> +#include <linux/hashtable.h>
>  #include <linux/io.h>
>  #include <linux/iopoll.h>
>  #include <linux/kernel.h>
>  #include <linux/mailbox_client.h>
>  #include <linux/module.h>
> +#include <linux/mutex.h>
>  #include <linux/of.h>
>  #include <linux/of_platform.h>
>  #include <linux/platform_device.h>
> @@ -87,6 +89,16 @@ struct ti_sci_desc {
>  	int max_msg_size;
>  };
>  
> +/**
> + * struct ti_sci_irq - Description of allocated irqs
> + * @node: Link to hash table
> + * @desc: Description of the irq
> + */
> +struct ti_sci_irq {
> +	struct hlist_node node;
> +	struct ti_sci_msg_req_manage_irq desc;
> +};
> +
>  /**
>   * struct ti_sci_info - Structure representing a TI SCI instance
>   * @dev:	Device pointer
> @@ -101,6 +113,8 @@ struct ti_sci_desc {
>   * @chan_rx:	Receive mailbox channel
>   * @minfo:	Message info
>   * @node:	list head
> + * @irqs:	List of allocated irqs
> + * @irq_lock:	Protection for irq hash list
>   * @host_id:	Host ID
>   * @fw_caps:	FW/SoC low power capabilities
>   * @users:	Number of users of this instance
> @@ -118,6 +132,8 @@ struct ti_sci_info {
>  	struct mbox_chan *chan_rx;
>  	struct ti_sci_xfers_info minfo;
>  	struct list_head node;
> +	DECLARE_HASHTABLE(irqs, 8);
> +	struct mutex irq_lock;

No action needed: checkpatch flags this as not documented, when it is
clearly documented above.

>  	u8 host_id;
>  	u64 fw_caps;
>  	/* protected by ti_sci_list_mutex */
> @@ -2301,6 +2317,32 @@ static int ti_sci_manage_irq(const struct ti_sci_handle *handle,
>  	return ret;
>  }
>  
> +/**
> + * ti_sci_irq_hash() - Helper API to compute irq hash for the hash table.
> + * @irq:	irq to hash
> + *
> + * Return: the computed hash value.
> + */
> +static int ti_sci_irq_hash(struct ti_sci_msg_req_manage_irq *irq)
> +{
> +	return irq->src_id ^ irq->src_index;
> +}
> +
> +/**
> + * ti_sci_irq_equal() - Helper API to compare two irqs (generic headers are not
> + *                       compared)
> + * @irq_a:	irq_a to compare
> + * @irq_b:	irq_b to compare
> + *
> + * Return: true if the two irqs are equal, else false.
> + */
> +static bool ti_sci_irq_equal(struct ti_sci_msg_req_manage_irq *irq_a,
> +			     struct ti_sci_msg_req_manage_irq *irq_b)
> +{
> +	return !memcmp(&irq_a->valid_params, &irq_b->valid_params,
> +		       sizeof(*irq_a) - sizeof(irq_a->hdr));
> +}
> +
>  /**
>   * ti_sci_set_irq() - Helper api to configure the irq route between the
>   *		      requested source and destination
> @@ -2324,15 +2366,60 @@ static int ti_sci_set_irq(const struct ti_sci_handle *handle, u32 valid_params,
>  			  u16 dst_host_irq, u16 ia_id, u16 vint,
>  			  u16 global_event, u8 vint_status_bit, u8 s_host)
>  {
> +	struct ti_sci_info *info = handle_to_ti_sci_info(handle);
> +	struct ti_sci_msg_req_manage_irq *desc;
> +	struct ti_sci_irq *irq;
> +	int ret;
> +
> +	/*
> +	 * Lock for set_irq() and free_irq() to keep the IRQ hash list
> +	 * consistent only if MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST is set. Else
> +	 * IRQ hash list is not used.
> +	 */
> +	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST)
> +		mutex_lock(&info->irq_lock);
> +
>  	pr_debug("%s: IRQ set with valid_params = 0x%x from src = %d, index = %d, to dst = %d, irq = %d,via ia_id = %d, vint = %d, global event = %d,status_bit = %d\n",
>  		 __func__, valid_params, src_id, src_index,
>  		 dst_id, dst_host_irq, ia_id, vint, global_event,
>  		 vint_status_bit);
>  
> -	return ti_sci_manage_irq(handle, valid_params, src_id, src_index,
> -				 dst_id, dst_host_irq, ia_id, vint,
> -				 global_event, vint_status_bit, s_host,
> -				 TI_SCI_MSG_SET_IRQ);
> +	ret = ti_sci_manage_irq(handle, valid_params, src_id, src_index,
> +				dst_id, dst_host_irq, ia_id, vint,
> +				global_event, vint_status_bit, s_host,
> +				TI_SCI_MSG_SET_IRQ);
> +
> +	if (ret || !(info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST))
> +		goto end;
> +
> +	irq = kzalloc_obj(*irq, GFP_KERNEL);
> +	if (!irq) {
> +		ti_sci_manage_irq(handle, valid_params, src_id, src_index,
> +				  dst_id, dst_host_irq, ia_id, vint,
> +				  global_event, vint_status_bit, s_host,
> +				  TI_SCI_MSG_FREE_IRQ);
> +		ret = -ENOMEM;
> +		goto end;
> +	}
> +
> +	desc = &irq->desc;
> +	desc->valid_params = valid_params;
> +	desc->src_id = src_id;
> +	desc->src_index = src_index;
> +	desc->dst_id = dst_id;
> +	desc->dst_host_irq = dst_host_irq;
> +	desc->ia_id = ia_id;
> +	desc->vint = vint;
> +	desc->global_event = global_event;
> +	desc->vint_status_bit = vint_status_bit;
> +	desc->secondary_host = s_host;
> +
> +	hash_add(info->irqs, &irq->node, ti_sci_irq_hash(desc));
> +
> +end:
> +	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST)
> +		mutex_unlock(&info->irq_lock);
> +	return ret;
>  }
>  
>  /**
> @@ -2358,15 +2445,56 @@ static int ti_sci_free_irq(const struct ti_sci_handle *handle, u32 valid_params,
>  			   u16 dst_host_irq, u16 ia_id, u16 vint,
>  			   u16 global_event, u8 vint_status_bit, u8 s_host)
>  {
> +	struct ti_sci_info *info = handle_to_ti_sci_info(handle);
> +	struct ti_sci_msg_req_manage_irq irq_desc;
> +	struct device *dev = info->dev;
> +	struct ti_sci_irq *this_irq;
> +	struct hlist_node *tmp_node;
> +	int ret;
> +
> +	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST)
> +		mutex_lock(&info->irq_lock);
> +
>  	pr_debug("%s: IRQ release with valid_params = 0x%x from src = %d, index = %d, to dst = %d, irq = %d,via ia_id = %d, vint = %d, global event = %d,status_bit = %d\n",
>  		 __func__, valid_params, src_id, src_index,
>  		 dst_id, dst_host_irq, ia_id, vint, global_event,
>  		 vint_status_bit);
>  
> -	return ti_sci_manage_irq(handle, valid_params, src_id, src_index,
> -				 dst_id, dst_host_irq, ia_id, vint,
> -				 global_event, vint_status_bit, s_host,
> -				 TI_SCI_MSG_FREE_IRQ);
> +	ret = ti_sci_manage_irq(handle, valid_params, src_id, src_index,
> +				dst_id, dst_host_irq, ia_id, vint,
> +				global_event, vint_status_bit, s_host,
> +				TI_SCI_MSG_FREE_IRQ);
> +
> +	if (ret || !(info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST))
> +		goto end;
> +
> +	irq_desc.valid_params = valid_params;
> +	irq_desc.src_id = src_id;
> +	irq_desc.src_index = src_index;
> +	irq_desc.dst_id = dst_id;
> +	irq_desc.dst_host_irq = dst_host_irq;
> +	irq_desc.ia_id = ia_id;
> +	irq_desc.vint = vint;
> +	irq_desc.global_event = global_event;
> +	irq_desc.vint_status_bit = vint_status_bit;
> +	irq_desc.secondary_host = s_host;
> +
> +	hash_for_each_possible_safe(info->irqs, this_irq, tmp_node, node,
> +				    ti_sci_irq_hash(&irq_desc)) {
> +		if (ti_sci_irq_equal(&irq_desc, &this_irq->desc)) {
> +			hlist_del(&this_irq->node);
> +			kfree(this_irq);
> +			goto end;
> +		}
> +	}
> +
> +	dev_warn(dev, "%s: should not be here, IRQ was not found in hash list\n",
> +		 __func__);
> +
> +end:
> +	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST)
> +		mutex_unlock(&info->irq_lock);
> +	return ret;
>  }
>  
>  /**
> @@ -3847,7 +3975,10 @@ static int ti_sci_suspend_noirq(struct device *dev)
>  static int ti_sci_resume_noirq(struct device *dev)
>  {
>  	struct ti_sci_info *info = dev_get_drvdata(dev);
> -	int ret = 0;
> +	struct ti_sci_msg_req_manage_irq *irq_desc;
> +	struct ti_sci_irq *irq;
> +	struct hlist_node *tmp_node;
> +	int ret = 0, err = 0, i;
>  	u32 source;
>  	u64 time;
>  	u8 pin;
> @@ -3859,13 +3990,50 @@ static int ti_sci_resume_noirq(struct device *dev)
>  			return ret;
>  	}
>  
> +	switch (pm_suspend_target_state) {
> +	case PM_SUSPEND_MEM:
> +		if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST) {
> +			hash_for_each_safe(info->irqs, i, tmp_node, irq, node) {
> +				irq_desc = &irq->desc;
> +				ret = ti_sci_manage_irq(&info->handle,
> +							irq_desc->valid_params,
> +							irq_desc->src_id,
> +							irq_desc->src_index,
> +							irq_desc->dst_id,
> +							irq_desc->dst_host_irq,
> +							irq_desc->ia_id,
> +							irq_desc->vint,
> +							irq_desc->global_event,
> +							irq_desc->vint_status_bit,
> +							irq_desc->secondary_host,
> +							TI_SCI_MSG_SET_IRQ);
> +				if (ret) {
> +					dev_err(dev, "failed to restore IRQ with valid_params = 0x%x from src = %d, index = %d, to dst = %d, irq = %d,via ia_id = %d, vint = %d, global event = %d,status_bit = %d\n",

space before via? overall this print is needed, but a bit umm.. we have
similar ones already..

> +						irq_desc->valid_params,
> +						irq_desc->src_id,
> +						irq_desc->src_index,
> +						irq_desc->dst_id,
> +						irq_desc->dst_host_irq,
> +						irq_desc->ia_id,
> +						irq_desc->vint,
> +						irq_desc->global_event,
> +						irq_desc->vint_status_bit);
> +					err = ret;
> +				}
> +			}
> +		}
> +		break;
> +	default:
> +		break;
> +	}
> +
>  	ret = ti_sci_msg_cmd_lpm_wake_reason(&info->handle, &source, &time, &pin, &mode);
>  	/* Do not fail to resume on error as the wake reason is not critical */
>  	if (!ret)
>  		dev_info(dev, "ti_sci: wakeup source:0x%x, pin:0x%x, mode:0x%x\n",
>  			 source, pin, mode);
>  
> -	return 0;
> +	return err;
>  }
>  
>  static void ti_sci_pm_complete(struct device *dev)
> @@ -4014,13 +4182,14 @@ static int ti_sci_probe(struct platform_device *pdev)
>  	}
>  
>  	ti_sci_msg_cmd_query_fw_caps(&info->handle, &info->fw_caps);
> -	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s%s\n",
> +	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s%s%s\n",
>  		info->fw_caps & MSG_FLAG_CAPS_GENERIC ? "Generic" : "",
>  		info->fw_caps & MSG_FLAG_CAPS_LPM_PARTIAL_IO ? " Partial-IO" : "",
>  		info->fw_caps & MSG_FLAG_CAPS_LPM_DM_MANAGED ? " DM-Managed" : "",
>  		info->fw_caps & MSG_FLAG_CAPS_LPM_ABORT ? " LPM-Abort" : "",
>  		info->fw_caps & MSG_FLAG_CAPS_IO_ISOLATION ? " IO-Isolation" : "",
> -		info->fw_caps & MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED ? " BoardConfig-Managed" : ""
> +		info->fw_caps & MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED ? " BoardConfig-Managed" : "",
> +		info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST ? " IRQ-Context-Lost" : ""
>  	);
>  
>  	ti_sci_setup_ops(info);
> @@ -4053,6 +4222,14 @@ static int ti_sci_probe(struct platform_device *pdev)
>  	list_add_tail(&info->node, &ti_sci_list);
>  	mutex_unlock(&ti_sci_list_mutex);
>  
> +	if (info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST) {
> +		ret = devm_mutex_init(dev, &info->irq_lock);
> +		if (ret)
> +			return ret;

If devm_mutex_init() fails, the function returns directly rather than
going through the out: label. All other error paths after the mailbox
channel allocations use goto out, which calls mbox_free_channel() for
both channels. Since mbox_request_channel_byname() is not a devm
allocation, those channels would not be freed by the devm cleanup path
on probe failure.

Does this leak info->chan_tx and info->chan_rx when devm_mutex_init()
returns an error?
> +
> +		hash_init(info->irqs);
> +	}
> +
>  	ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
>  	if (ret) {
>  		dev_err(dev, "platform_populate failed %pe\n", ERR_PTR(ret));
> diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
> index d90de59e29eb..67f16e8c69a1 100644
> --- a/drivers/firmware/ti_sci.h
> +++ b/drivers/firmware/ti_sci.h
> @@ -151,6 +151,7 @@ struct ti_sci_msg_req_reboot {
>   *		MSG_FLAG_CAPS_LPM_ABORT: Abort entry to LPM
>   *		MSG_FLAG_CAPS_IO_ISOLATION: IO Isolation support
>   *		MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED: LPM config done statically for the DM via boardcfg
> + *		MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST: DM is not able to restore IRQ context
>   *
>   * Response to a generic message with message type TI_SCI_MSG_QUERY_FW_CAPS
>   * providing currently available SOC/firmware capabilities. SoC that don't
> @@ -164,6 +165,7 @@ struct ti_sci_msg_resp_query_fw_caps {
>  #define MSG_FLAG_CAPS_LPM_ABORT		TI_SCI_MSG_FLAG(9)
>  #define MSG_FLAG_CAPS_IO_ISOLATION	TI_SCI_MSG_FLAG(7)
>  #define MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED	TI_SCI_MSG_FLAG(12)
> +#define MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST	TI_SCI_MSG_FLAG(14)
>  #define MSG_MASK_CAPS_LPM		GENMASK_ULL(4, 1)
>  	u64 fw_caps;
>  } __packed;
> 
> -- 
> 2.53.0
> 

-- 
Regards,
Nishanth Menon
Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3  1A34 DDB5 849D 1736 249D
https://ti.com/opensource

[PATCH v7 3/4] clk: keystone: sci-clk: add restore_context() operation

[Thomas Richard (TI)]

Implement the restore_context() operation to restore the clock rate and the
clock parent state. The clock rate is saved in sci_clk struct during
set_rate() and recalc_rate() operations. The parent index is saved in
sci_clk struct during set_parent() operation. During clock registration,
the core retrieves each clock’s parent using get_parent() operation to
ensure the internal clock tree reflects the actual hardware state,
including any configurations made by the bootloader. So we also save the
parent index in get_parent().

Reviewed-by: Dhruva Gole <d-gole@ti.com>
Reviewed-by: Kendall Willis <k-willis@ti.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Thomas Richard (TI) <thomas.richard@bootlin.com>
---
 drivers/clk/keystone/sci-clk.c | 45 ++++++++++++++++++++++++++++++++++--------
 1 file changed, 37 insertions(+), 8 deletions(-)

diff --git a/drivers/clk/keystone/sci-clk.c b/drivers/clk/keystone/sci-clk.c
index 9d5071223f4c..7c0f7b3e89e0 100644
--- a/drivers/clk/keystone/sci-clk.c
+++ b/drivers/clk/keystone/sci-clk.c
@@ -47,6 +47,8 @@ struct sci_clk_provider {
  * @node:	 Link for handling clocks probed via DT
  * @cached_req:	 Cached requested freq for determine rate calls
  * @cached_res:	 Cached result freq for determine rate calls
+ * @parent_id:	 Parent index for this clock
+ * @rate:	 Clock rate
  */
 struct sci_clk {
 	struct clk_hw hw;
@@ -58,6 +60,8 @@ struct sci_clk {
 	struct list_head node;
 	unsigned long cached_req;
 	unsigned long cached_res;
+	int parent_id;
+	unsigned long rate;
 };
 
 #define to_sci_clk(_hw) container_of(_hw, struct sci_clk, hw)
@@ -150,6 +154,8 @@ static unsigned long sci_clk_recalc_rate(struct clk_hw *hw,
 		return 0;
 	}
 
+	clk->rate = freq;
+
 	return freq;
 }
 
@@ -210,10 +216,15 @@ static int sci_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 			    unsigned long parent_rate)
 {
 	struct sci_clk *clk = to_sci_clk(hw);
+	int ret;
 
-	return clk->provider->ops->set_freq(clk->provider->sci, clk->dev_id,
-					    clk->clk_id, rate / 10 * 9, rate,
-					    rate / 10 * 11);
+	ret = clk->provider->ops->set_freq(clk->provider->sci, clk->dev_id,
+					   clk->clk_id, rate / 10 * 9, rate,
+					   rate / 10 * 11);
+	if (!ret)
+		clk->rate = rate;
+
+	return ret;
 }
 
 /**
@@ -234,12 +245,13 @@ static u8 sci_clk_get_parent(struct clk_hw *hw)
 		dev_err(clk->provider->dev,
 			"get-parent failed for dev=%d, clk=%d, ret=%d\n",
 			clk->dev_id, clk->clk_id, ret);
+		clk->parent_id = ret;
 		return 0;
 	}
 
-	parent_id = parent_id - clk->clk_id - 1;
+	clk->parent_id = parent_id - clk->clk_id - 1;
 
-	return (u8)parent_id;
+	return (u8)clk->parent_id;
 }
 
 /**
@@ -252,12 +264,28 @@ static u8 sci_clk_get_parent(struct clk_hw *hw)
 static int sci_clk_set_parent(struct clk_hw *hw, u8 index)
 {
 	struct sci_clk *clk = to_sci_clk(hw);
+	int ret;
 
 	clk->cached_req = 0;
 
-	return clk->provider->ops->set_parent(clk->provider->sci, clk->dev_id,
-					      clk->clk_id,
-					      index + 1 + clk->clk_id);
+	ret = clk->provider->ops->set_parent(clk->provider->sci, clk->dev_id,
+					     clk->clk_id,
+					     index + 1 + clk->clk_id);
+	if (!ret)
+		clk->parent_id = index;
+
+	return ret;
+}
+
+static void sci_clk_restore_context(struct clk_hw *hw)
+{
+	struct sci_clk *clk = to_sci_clk(hw);
+
+	if (clk->num_parents > 1 && clk->parent_id >= 0)
+		sci_clk_set_parent(hw, (u8)clk->parent_id);
+
+	if (clk->rate)
+		sci_clk_set_rate(hw, clk->rate, 0);
 }
 
 static const struct clk_ops sci_clk_ops = {
@@ -269,6 +297,7 @@ static const struct clk_ops sci_clk_ops = {
 	.set_rate = sci_clk_set_rate,
 	.get_parent = sci_clk_get_parent,
 	.set_parent = sci_clk_set_parent,
+	.restore_context = sci_clk_restore_context,
 };
 
 /**

-- 
2.53.0

[PATCH v7 4/4] firmware: ti_sci: add support for restoring clock context during resume

[Thomas Richard (TI)]

Some DM-Firmware are not able to restore the clock rates and the clock
parents after a suspend-resume. The CLK_CONTEXT_LOST firmware capability
has been introduced to identify this characteristic. In this case the
responsibility is therefore delegated to the ti_sci driver, which uses
clk_restore_context() to trigger the context_restore() operation for all
registered clocks, including those managed by the sci-clk. The sci-clk
driver implements the context_restore() operation to ensure rates and clock
parents are correctly restored.

Reviewed-by: Dhruva Gole <d-gole@ti.com>
Reviewed-by: Kendall Willis <k-willis@ti.com>
Signed-off-by: Thomas Richard (TI) <thomas.richard@bootlin.com>
---
 drivers/firmware/ti_sci.c | 9 +++++++--
 drivers/firmware/ti_sci.h | 2 ++
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index 531ac3aa38b8..1ee8f67d3f7e 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -9,6 +9,7 @@
 #define pr_fmt(fmt) "%s: " fmt, __func__
 
 #include <linux/bitmap.h>
+#include <linux/clk.h>
 #include <linux/cpu.h>
 #include <linux/debugfs.h>
 #include <linux/export.h>
@@ -4022,6 +4023,9 @@ static int ti_sci_resume_noirq(struct device *dev)
 				}
 			}
 		}
+
+		if (info->fw_caps & MSG_FLAG_CAPS_LPM_CLK_CONTEXT_LOST)
+			clk_restore_context();
 		break;
 	default:
 		break;
@@ -4182,14 +4186,15 @@ static int ti_sci_probe(struct platform_device *pdev)
 	}
 
 	ti_sci_msg_cmd_query_fw_caps(&info->handle, &info->fw_caps);
-	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s%s%s\n",
+	dev_dbg(dev, "Detected firmware capabilities: %s%s%s%s%s%s%s%s\n",
 		info->fw_caps & MSG_FLAG_CAPS_GENERIC ? "Generic" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_PARTIAL_IO ? " Partial-IO" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_DM_MANAGED ? " DM-Managed" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_ABORT ? " LPM-Abort" : "",
 		info->fw_caps & MSG_FLAG_CAPS_IO_ISOLATION ? " IO-Isolation" : "",
 		info->fw_caps & MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED ? " BoardConfig-Managed" : "",
-		info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST ? " IRQ-Context-Lost" : ""
+		info->fw_caps & MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST ? " IRQ-Context-Lost" : "",
+		info->fw_caps & MSG_FLAG_CAPS_LPM_CLK_CONTEXT_LOST ? " Clk-Context-Lost" : ""
 	);
 
 	ti_sci_setup_ops(info);
diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
index 67f16e8c69a1..2d75667a6723 100644
--- a/drivers/firmware/ti_sci.h
+++ b/drivers/firmware/ti_sci.h
@@ -152,6 +152,7 @@ struct ti_sci_msg_req_reboot {
  *		MSG_FLAG_CAPS_IO_ISOLATION: IO Isolation support
  *		MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED: LPM config done statically for the DM via boardcfg
  *		MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST: DM is not able to restore IRQ context
+ *		MSG_FLAG_CAPS_LPM_CLK_CONTEXT_LOST: DM is not able to restore Clock context
  *
  * Response to a generic message with message type TI_SCI_MSG_QUERY_FW_CAPS
  * providing currently available SOC/firmware capabilities. SoC that don't
@@ -166,6 +167,7 @@ struct ti_sci_msg_resp_query_fw_caps {
 #define MSG_FLAG_CAPS_IO_ISOLATION	TI_SCI_MSG_FLAG(7)
 #define MSG_FLAG_CAPS_LPM_BOARDCFG_MANAGED	TI_SCI_MSG_FLAG(12)
 #define MSG_FLAG_CAPS_LPM_IRQ_CONTEXT_LOST	TI_SCI_MSG_FLAG(14)
+#define MSG_FLAG_CAPS_LPM_CLK_CONTEXT_LOST	TI_SCI_MSG_FLAG(15)
 #define MSG_MASK_CAPS_LPM		GENMASK_ULL(4, 1)
 	u64 fw_caps;
 } __packed;

-- 
2.53.0